Composition of matter to be used in the manufacture of imitation leaded glass.



UNITED sTATEs PATENT OFFICE.

ARTHUR ERNEST BERNASCONI, OF COVENTRY, ENGLAND.

COMPOSITION OF MATTER TO BE USED IN THE MANUFACTURE OF IMITATION LEADEDPatented Aug. 2, 1910.

GLASS.

965,860. Specification of Letters Patent.

No Drawing.

To all whom it may concern:

Be it known that I, ARTHUR ERNEST BERN- ASCONI, a subject of the King ofGreat Britain, and resident of Coventry, in the county of Warwick,England, have invented a new and useful Composition of Matter to be Usedin the Manufacture of Imitation Leaded Glass, of which the following isa specification.

This invention relates to improvements in imitation leaded glass, andhas for its object the production of a composition for forming theoutlines, which when fired will unite with the glass and resemblestrongly leaded outlining.

According to this invention, the composition consists of a mixture ofchina clay, glass flux, and black enamel. With this is mixed a littleadhesive such as gum arabic by which it can be caused to adhere to theglass. The outlining may be applied to both sides of the glass, which isthen fired or baked in a kiln, causing the composition used for thelines to fuse. When fired the lines harden and unite with the glass.

For the composition of the mixture of which the outlining is composedthe following proportions have been found suitable z- 1 part of hardblack enamel, known to the British glass trade as No. 31 F. 2 parts ofchina clay No. 100. 1 parts of glass flux known to the trade as No. 157F. The hard black enamel above mentioned is composed of silica, potash,borax, manganese and black oxid of copper. The china clay is the bestwhite china clay used for china. The glass flux is a compound of silica,borax, potash and lead. These are thoroughly mixed but the compositionwill not adhere'to glass well by itself. To overcome this it is mixedwith gum arabic and water, a sufficient quantity being used to enablethe mixture to adhere to the glass in any desired quantity until theglass is burnt. The gum arabic is only used as an adhesive.

In carrying out the invention a sheet of glass of any suitable kind isplaced over a design, and the mixture traced on the glass over thedesign, in any suitable manner. For instance, it may be applied with astick, brush, or tube. A sufficient quantity is applied to make thelines stand up, after which the glass is allowed to dry when it can beturned over and the opposite side similarly treated. When thoroughly drythe sheet of Application filed July 31, 1909.

Serial No. 510,565.

glass is placed in a cast iron tray and bedded down on a bed of plasterof paris, and is then covered by a lid, which leaves a clearance ofabout four inches. Thus a large body of air is interposed between theglass and the lid, enabling the firing to be efiected slowly in thewell-known manner.

Preferably the kiln is formed with a view hole so that the condition ofthe glass can be examined from time to time. As soon as the lines turnto a dark grey color the glass can be removed and it will be found thatthe lines have set hard, having exactly the same appearance as thepartitions used in leaded glass. Conveniently the kiln is so constructedthat the tray containing the glass, directly it is treated, can beremoved from the back of the kiln and a fresh tray inserted and so oncontinuously.

In making colored glass the'stains are applied to the surface of thesheet of glass either before or after the outlining has been done andpreferably such stains are chosen as fuse at the same temperature as themixture used in the lines, as has hitherto been proposed. If desiredhowever, the proportions of the composition of the mixture may be variedto make it fuse at the temperature of the stains. The stains can beapplied to either or both sides of the glass enabling different shadesto be obtained.

By the use of the composition above described both sides of the glasscan be treated without damage tothe composition before it is burnt,or'during the process of burning.

It is found that with this composition the glass ready for firing may bebedded down upon plaster of paris or the like without the compositionadhering to the bed. This is a point of great importance as it enablesboth sides of the glass to be treated equally well, and obviates thenecessity for standing the glass on edge, which causes it to warp.

Obviously the rate of firing may vary according to circumstances, butpreferably it is somewhat slow. Again, the composition of the mixturemay be varied without departing from the invention. The aboveproportions have been found to effect the pur pose satisfactorily.

That I claim as my invention, and desire to secure by Letters Patentis 1. The herein described composition of matter comprising black enamel(consisting of silica, potash, borax, manganese, and

black oxid of copper), china clay, and glass and lead), mixed with anadhesive before flux (consisting of a compound of silica, fusing,substantially as and for the purpose borax, potash and lead),substantially as described and for the purpose described. In testimonywhereof I have signed my 5 2. The herein described composition of nameto this specification in the presence of 15 matter for imitation leadedglass, compristwo subscribing Witnesses.

ing black enamel (consisting of silica, pot- ARTHUR ERNEST BERNASCONI.ash, borax, manganese, and black oxid of Witnesses: copper), china clay,andglass flux (consist- J OHN I. FAZAKARLEY,

10 ing of a compound of sllica, borax, potash HORACE D. TINGEY.

